STMicroelectronics FlexSPIN: SPI configurable stepper and DC multi motor driver evaluation board EVAL6460 EVAL6460 Data Sheet

   

   

   

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 Doc ID 17713 Rev 1

The linear main regulator is directly powered by V

Supply

 voltage and it is one of the 

regulators that L6460 could consider as a system regulator. This means that the voltage 
generated by this regulator is not used to power any internal circuit, but L6460 will check 
that the feedback voltage V

LINmain_FB

 is in the good value range before enabling all its 

internal functions. When an under-voltage event (with a duration longer than period t

prim_uv

 

defined by the deglitch filter) is detected during normal operation, L6460 will enter in reset 
state and it will signal this event to the microcontroller by pulling low the nRESET pin and 
disabling most of its internal blocks.

Here are summarized the primary features of the regulator:

–

Regulated output voltage from 0.8V to V

Supply

-2V with a maximum load of 10mA.

–

Band gap generated internal reference voltage.

–

Short circuit protected (output current is clamped to 22mA typ).

–

Under voltage signal (both continuous and latched) accessible through serial 
interface.

–

Low power dissipation mode.

The internal series element is a P-channel MOS device. The voltage regulator will regulate 
its output so that feedback pin equals V

LINmain_FB

, therefore the regulated voltage can be 

calculated using the formula:

V

LINmain_OUT

 = V

LINmain_ref

 *(R

a

+R

b

)/R

b

To extend the output current capability this regulator can be used as a controller for an 
external active component able to provide higher current (i.e. a Darlington device); the 
external power element allows the handling of an higher current since it dissipates the 
power externally (the power dissipated by a linear driver supplied at V

Supply

 and regulating a 

voltage V

LINmain_OUT

 with an output current I

OUT

 is about: P

d

= (V

Supply

-V

LINmain_OUT

)*I

OUT

.

 

Dri

v

e

r 

V

LINmain_ref 

Cc 

R

a

 

R

b

 

+ 

- 

Body Diode

 

V

supply 

V

LINmain_OUT 

V

LINmain_FB